Anal adenocarcinoma requires prophylactic inguinal nodal treatment: Results from a single Chinese institution

BACKGROUND Literature pertaining to prophylactic inguinal nodal treatment for anal adenocarcinoma in China is scarce. METHODS In this retrospective study, we analyzed 126 patients from 1965 to 2015. Among these, 67 patients received surgery only, 18 patients received chemoradiotherapy only, 27 patients received a combination of both, and the remaining 14 patients received palliative treatment. RESULTS The median follow up period was 30 months. The 1-year, 3-year, and 5-year overall survival rates were 85.8%, 62.5%, and 43.4%, respectively. The 5-year overall survival was 46.9% for patients with negative inguinal lymph nodes and 19.1% for patients with positive inguinal lymph nodes (p=0.007). The overall 5-year inguinal node relapse-free survival was 83.0%. The 5-year inguinal node relapse-free survival was 87.5% for stage I, 86.9% for stage II, and 76.5% for stage III cancers. Among those with negative inguinal nodes, the 5-year inguinal node relapse-free survival was 85.7% for negative regional lymph nodes and 75.4% for positive regional lymph nodes (p=0.089). CONCLUSION Inguinal lymph node is a high-risk subclinical area. Prophylactic inguinal nodal treatment is necessary for patients with anal adenocarcinoma irrespective of positive or negative inguinal lymph nodes.